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<a name="GdaLockable"></a><div class="titlepage"></div>
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<h2><span class="refentrytitle"><a name="GdaLockable.top_of_page"></a>GdaLockable</span></h2>
<p>GdaLockable — Interface for locking objects in a multi threaded environment</p>
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<div class="refsect1">
<a name="GdaLockable.stability-level"></a><h2>Stability Level</h2>
<a href="http://foldoc.org/Stable"><span class="acronym">Stable</span></a>, unless otherwise indicated
</div>
<div class="refsect1">
<a name="GdaLockable.functions"></a><h2>Functions</h2>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="functions_proto_type">
<col class="functions_proto_name">
</colgroup>
<tbody>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="GdaLockable.html#gda-lockable-lock" title="gda_lockable_lock ()">gda_lockable_lock</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
</td>
<td class="function_name">
<a class="link" href="GdaLockable.html#gda-lockable-trylock" title="gda_lockable_trylock ()">gda_lockable_trylock</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="GdaLockable.html#gda-lockable-unlock" title="gda_lockable_unlock ()">gda_lockable_unlock</a> <span class="c_punctuation">()</span>
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<div class="refsect1">
<a name="GdaLockable.other"></a><h2>Types and Values</h2>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="other_proto_type">
<col class="other_proto_name">
</colgroup>
<tbody><tr>
<td class="datatype_keyword"> </td>
<td class="function_name"><a class="link" href="GdaLockable.html#GdaLockable-struct" title="GdaLockable">GdaLockable</a></td>
</tr></tbody>
</table></div>
</div>
<div class="refsect1">
<a name="GdaLockable.object-hierarchy"></a><h2>Object Hierarchy</h2>
<pre class="screen">    <a href="/usr/share/gtk-doc/html/gobject/GTypeModule.html">GInterface</a>
    <span class="lineart">╰──</span> GdaLockable
</pre>
</div>
<div class="refsect1">
<a name="GdaLockable.prerequisites"></a><h2>Prerequisites</h2>
<p>
GdaLockable requires
 <a href="/usr/share/gtk-doc/html/gobject/gobject-The-Base-Object-Type.html#GObject-struct">GObject</a>.</p>
</div>
<div class="refsect1">
<a name="GdaLockable.implementations"></a><h2>Known Implementations</h2>
<p>
GdaLockable is implemented by
 <a class="link" href="GdaConnection.html" title="GdaConnection">GdaConnection</a>,  <a class="link" href="GdaHolder.html" title="GdaHolder">GdaHolder</a>,  <a class="link" href="GdaLdapConnection.html" title="GdaLdapConnection">GdaLdapConnection</a>,  <a class="link" href="GdaSqlParser.html" title="GdaSqlParser">GdaSqlParser</a>,  <a class="link" href="GdaVconnectionDataModel.html" title="GdaVconnectionDataModel">GdaVconnectionDataModel</a>,  <a class="link" href="GdaVconnectionHub.html" title="GdaVconnectionHub">GdaVconnectionHub</a> and  <a class="link" href="GdaVirtualConnection.html" title="GdaVirtualConnection">GdaVirtualConnection</a>.</p>
</div>
<div class="refsect1">
<a name="GdaLockable.includes"></a><h2>Includes</h2>
<pre class="synopsis">#include &lt;libgda/gda-statement-extra.h&gt;
</pre>
</div>
<div class="refsect1">
<a name="GdaLockable.description"></a><h2>Description</h2>
<p>This interface is implemented by objects which are thread safe (ie. can be used by several threads at
the same time). Before using an object from a thread, one has to call <a class="link" href="GdaLockable.html#gda-lockable-lock" title="gda_lockable_lock ()"><code class="function">gda_lockable_lock()</code></a> or
<a class="link" href="GdaLockable.html#gda-lockable-trylock" title="gda_lockable_trylock ()"><code class="function">gda_lockable_trylock()</code></a> and call <a class="link" href="GdaLockable.html#gda-lockable-unlock" title="gda_lockable_unlock ()"><code class="function">gda_lockable_unlock()</code></a> when the object is not used anymore.</p>
</div>
<div class="refsect1">
<a name="GdaLockable.functions_details"></a><h2>Functions</h2>
<div class="refsect2">
<a name="gda-lockable-lock"></a><h3>gda_lockable_lock ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gda_lockable_lock (<em class="parameter"><code><a class="link" href="GdaLockable.html" title="GdaLockable"><span class="type">GdaLockable</span></a> *lockable</code></em>);</pre>
<p>Locks <em class="parameter"><code>lockable</code></em>
. If it is already locked by another thread, the current thread will block until it is unlocked 
by the other thread.</p>
<p>This function can be used even if <a href="/usr/share/gtk-doc/html/glib/glib-Deprecated-Thread-APIs.html#g-thread-init"><code class="function">g_thread_init()</code></a> has not yet been called, and, in that case, will do nothing.</p>
<p>Note: unlike <a href="/usr/share/gtk-doc/html/glib/glib-Threads.html#g-mutex-lock"><code class="function">g_mutex_lock()</code></a>, this method recursive, which means a thread can lock <em class="parameter"><code>lockable</code></em>
 several times 
(and has to unlock it as many times to actually unlock it).</p>
<div class="refsect3">
<a name="gda-lockable-lock.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>lockable</p></td>
<td class="parameter_description"><p>a <a class="link" href="GdaLockable.html" title="GdaLockable"><span class="type">GdaLockable</span></a> object.</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gda-lockable-trylock"></a><h3>gda_lockable_trylock ()</h3>
<pre class="programlisting"><a href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a>
gda_lockable_trylock (<em class="parameter"><code><a class="link" href="GdaLockable.html" title="GdaLockable"><span class="type">GdaLockable</span></a> *lockable</code></em>);</pre>
<p>Tries to lock <em class="parameter"><code>lockable</code></em>
. If it is already locked by another thread, then it immediately returns FALSE, otherwise
it locks <em class="parameter"><code>lockable</code></em>
.</p>
<p>This function can be used even if <a href="/usr/share/gtk-doc/html/glib/glib-Deprecated-Thread-APIs.html#g-thread-init"><code class="function">g_thread_init()</code></a> has not yet been called, and, in that case, will do nothing.</p>
<p>Note: unlike <a href="/usr/share/gtk-doc/html/glib/glib-Threads.html#g-mutex-lock"><code class="function">g_mutex_lock()</code></a>, this method recursive, which means a thread can lock <em class="parameter"><code>lockable</code></em>
 several times 
(and has to unlock it as many times to actually unlock it).</p>
<div class="refsect3">
<a name="gda-lockable-trylock.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>lockable</p></td>
<td class="parameter_description"><p>a <a class="link" href="GdaLockable.html" title="GdaLockable"><span class="type">GdaLockable</span></a> object.</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="gda-lockable-trylock.returns"></a><h4>Returns</h4>
<p> TRUE if the object has successfully been locked.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gda-lockable-unlock"></a><h3>gda_lockable_unlock ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
gda_lockable_unlock (<em class="parameter"><code><a class="link" href="GdaLockable.html" title="GdaLockable"><span class="type">GdaLockable</span></a> *lockable</code></em>);</pre>
<p>Unlocks <em class="parameter"><code>lockable</code></em>
. This method should not be called if the current does not already holds a lock on <em class="parameter"><code>lockable</code></em>
 (having
used <a class="link" href="GdaLockable.html#gda-lockable-lock" title="gda_lockable_lock ()"><code class="function">gda_lockable_lock()</code></a> or <a class="link" href="GdaLockable.html#gda-lockable-trylock" title="gda_lockable_trylock ()"><code class="function">gda_lockable_trylock()</code></a>).</p>
<p>This function can be used even if <a href="/usr/share/gtk-doc/html/glib/glib-Deprecated-Thread-APIs.html#g-thread-init"><code class="function">g_thread_init()</code></a> has not yet been called, and, in that case, will do nothing.</p>
<div class="refsect3">
<a name="gda-lockable-unlock.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>lockable</p></td>
<td class="parameter_description"><p>a <a class="link" href="GdaLockable.html" title="GdaLockable"><span class="type">GdaLockable</span></a> object.</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
</div>
<div class="refsect1">
<a name="GdaLockable.other_details"></a><h2>Types and Values</h2>
<div class="refsect2">
<a name="GdaLockable-struct"></a><h3>GdaLockable</h3>
<pre class="programlisting">typedef struct _GdaLockable GdaLockable;</pre>
</div>
</div>
<div class="refsect1">
<a name="GdaLockable.see-also"></a><h2>See Also</h2>
<p><a class="link" href="libgda-5.0-GdaMutex.html#GdaMutex" title="GdaMutex"><span class="type">GdaMutex</span></a> and <a href="/usr/share/gtk-doc/html/glib/glib-Threads.html#GMutex"><span class="type">GMutex</span></a></p>
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